Electromagnetic stapler

ABSTRACT

This electro-magnetic stapler is hand held and has a circuit including a trigger switch, which when actuated, energizes an electro-magnetic load coil to operate the stapler. When the trigger is held in an actuated condition for sufficient time the operation of the stapler is repeated. A safety switch controlled by work engaging means on the stapler, prevents operation of the stapler unless said work engaging means contacts the work piece. The staple driving blade is at the front end of the stapler to facilitate locating the stapler relative to the place where the stapling is to be done. The trigger switch assembly permits a smooth operation. The assembly of the stapler permits a pair of split plastic covers to be removed without effecting the innards of the stapler. The plunger movement is shock absorbed at opposite ends of its movement. The circuit parts and components are housed in the stapler and mounted on a non-conductive plate disposed in the handle portion of the stapler.

Manganaro [111 3,786,978 [451 Jan. 22, 1974 4] ELECTROMAGNETIC STAPLER[75] Inventor: George F. Manganaro, Lake Hiawatha, NJ.

[73] Assignee: Electro-Matic Staplers, Inc.,

Woodcliff Lake, NJ.

[22] Filed: June 5, 1972 [21] Appl. No.: 259,398

Primary ExaminerGranville Y. Custer, Jr.

Attorney, Agent, or Firm-Marvin Feldman; J. B. Felshin [5 7] ABSTRACTThis electro-magnetic stapler is hand held and has a circuit including atrigger switch, which when actuated, energizes an electro-magnetic loadcoil to operate the stapler. When the trigger is held in an actuatedcondition for sufficient time the operation of the stapler is repeated.A safety switch controlled by work engaging means on the stapler,prevents operation of the stapler unless said work engaging meanscontacts the work piece. The staple driving blade is at the front end ofthe stapler to facilitate locating the stapler relative to the placewhere the stapling is to be done. The trigger switch assembly permits asmooth operation. The assembly of the stapler permits a pair of splitplastic covers to be removed without effecting the innards of thestapler. The plunger movement is shock absorbed at opposite ends of itsmovement. The circuit parts and components are housed in the stapler andmounted on a non-conductive plate disposed in the handle portion of thestapler.

24 Claims, 9 Drawing Figures PATENTEB 24221914 SREEIIUFII FIGQ PATENTED3.786.978

sum t [If 4 ELECTROMAGNETIC STAPLER This invention relates toelectro-magnetic staplers.

One object of this invention is to improve the electromagnetic staplerdisclosed in US. Pat. No. 3,589,587, granted June 29, 1971.

Another object of this invention is to provide a stapler of thecharacter described, provided with safety means to prevent operation ofthe stapler upon actuating the trigger unless the stapler is positionedon the work piece, to prevent accidental operation of the stapler.

Yet another object of this invention is to provide a stapler of thecharacter described in which the staple driving blade is at the frontend of the stapler so as to facilitate location of the point at whichthe stapling takes place.

Still another object of this invention is to provide an electro-magneticstapler of the character described which shall be relatively easy toassemble, in which the components of the control circuit are mounted ona non-conductive member affixed to the metal frame of the stapler andhoused in the handle portion of the stapler and in which the metal frameis housed in split plastic half-covers attached together and to theframe so as to house the frame.

Yet another object of this invention is to provide in an electromagneticstapler of the character described, a highly improved trigger whichshall be easy to actuate and which shall readily return to normal,unactuated condition, when released, and which when actuated, shallclose a switch to control energization of an electro-magnet to operatethe stapler.

A further object of this invention is to provide a strong and durablestapler of the character described which shall be positive in operationand which shall yet be practical, safe and efficient to a high degree inuse.

Other objects of this invention will in part be obvious, and in parthereinafter be pointed out.

This invention accordingly consists in the features of construction,combinations of elements, and arrangement of parts which will beexemplified in the construction hereinafter described, and of which thescope of invention will be indicated in the following claims.

In the drawings:

FIG. 1 is a side elevational view of an electromagnetic staplerembodying the invention, with parts broken away and in cross-section;

FIG. 2 is a cross-sectional view taken on line 2-2 of FIG. 1;

FIG. 3 is a cross-sectional view taken on line 3-3 of FIG. 1;

FIG. 4 is a front elevational view of the stapler;

FIG. 5 is a side elevational view of the stapler with the coversremoved;

FIG. 6 is a top plan view of the structure shown in FIG. 5;

FIG. 7 is a crosssectional view taken on line 7-7 of FIG. 5;

FIG. 8 is a cross-sectional view' taken on line 8-8 of FIG. 5 and;

FIG. 9 is a wiring diagram of the circuit for controlling theelectro-magnet which operates the staple driving blade or knife:

Referring now in detail to the drawings, 10 designates anelectro-magnetically controlled stapler embodying the invention. Saidstapler 10 comprises a metal body 11 made of two symmetrical,substantially similar metal frame members 12 and 13.

Frame member 12 comprises a horizontally extending lower wall portion12a disposed in a vertical plane and having an upper horizontal edge12b, a lower horizontal edge 12c and a rear edge 12d. At the forward endof wall 12a is an outwardly bent portion 12f from which there extendsforwardly a downwardly and inwardly converging inclined wall 12g.

Member 12 further comprises a vertical wall 12h disposed forwardly andabove wall 12f and outwardly of the plane of wall 12a. Wall 12h extendsupwardly and forwardly and comprises portions 12hl. Extending from wall1211 is a part cylindrical wall 12j joined to wall 12g by a lowershoulder 12k and to wall portion 12h3 by a top shoulder 12m. Wallportion l2h2 is disposed forwardly of wall l2j; wall portion l2h3 isdisposed above shoulder 12m and wall portion 12h] is disposed rearwardlyof wall 12j. Extending inwardly from the rear side of the upper end ofpart cylindrical wall 12j is a shoulder 1214, from which extendsrearwardly a vertical flange 12w in the plane of wall 12a.

Frame member 12 also has a top horizontal flange 12n and a rear verticalflange 12p. Frame member 12 also has a rear upstanding arm 12x. Framemember 13 is like member 12 and is fixed thereto in spaced, syrnmetricalrelation, in the manner hereinafter appearing. Parts of member 13corresponding to similar parts of member 12 are designated by numeral I3followed by a corresponding letter, the same way that the parts ofmember 12 are designated.

Wall portion 12h has a vertical front edge 12s, and a secondintermediate vertical edge 12! disposed somewhat rearwardly of saidfront edge. Portions 12h, 13h of frame members 12, 13 form part of afront head for the stapler, as will appear hereinafter. Disposed betweenthe flange l2w and the corresponding flange 13w of member 13, is atrigger housing 15 made of plastic, open at its underside and having ahorizontal wall 15a from which extends downwardly, a front wall 15b, arear wall 15c and side parallel walls 15d forming a socket open at thebottom and in which a trigger member 18 is slidably mounted. Trigger 18projects below the trigger housing. Extending up from horizontal wall15a is a flange 15f lying against the inner surface of flange 12w. Anon-conducting plastic plate 17 disposed in a verical plane, and in theshape of a handle, has one end at the inner surface of the flange 13w offrame member 13 and its other end contacts the inner surface of arm 13aof member 13. Between the forward end of plate 17 and flange 15f oftrigger housing 15, is a micro-switch 28 provided at its underside witha switch actuator button 29 projecting down through a hole 20 in wall15a.

Trigger 18 has limited sliding, up and down movement in the triggerhousing socket. To this end, one wall 15d of the housing has a verticalslot 22 receiving a transverse pin 23 on the trigger. The lower end ofthe trigger is curved upwardly as at 18a and projects below the triggerhousing 15. Said trigger has two upwardly opening bores 18b receivingcompression springs 23a, 24 which bias the trigger downwardly to anonoperative position. One of the bores 18b is aligned with opening 20.A switch acutating member 24a rests on the spring 23 in the bore whichis aligned with the opening 20 and actuator button 29 to operate saidbutton when the trigger is pulled up.

The plate 17 and micro-switch 28 are fixed to flange f, flange 12w ofmember 12 and the corresponding flange 13w of member 13 by transversescrews 25.

The trigger housing 15 is formed with a pair of opposed, outwardlyextending lugs 15h, which engage complimentary flange 13w of member 13,to properly position the trigger housing relative to frame 12.

Fitted over the front of frame 12 is a front metal cover member 30. Saidmember 30 comprises a front wall 31 contacting front edges 12s and 13sof the frame members 12,13, respectively. Extending rearwardly from theside of front wall 31 are side flanges 32 contacting outer adjacentsurfaces of frame members 12,13. Front wall 31 has two vertical slots 33near its lower end to receive front ends of a staple magazine, as willbe explained hereinafter. The lower ends of side walls 32 are inclineddownwardly and inwardly, as at 34. Walls 34 extend rearwardly and haveupwardly extendingears 35 formed with openings 36 registering withsimilar openings in walls 12h! and 13111 of members 12, 13 respectively.

Front wall 31 of cover 30 has a forwardly recessed, central, verticalportion 31a'terminating short of the upper and lower ends of said frontwall.

Surrounding the frame members 12, 13 and the front cover 30 are a pairof similar, symmetrical, heat and electrical insulating cover members 40having meeting edges 41 along a central vertical plane. Said members 40have lower horizontal portions 40a, front portions 40b, and handleportions 40c so as to form a hand hole 42 into which the trigger 18projects. The cover members 40 are fixed to each other and to the framemembers 12, 13 by a transverse bolt or rod 44 passing through openings32b, bolt or rod 45 passing through openings 36, and bolt or rod 46passing through a hole 47m plate 17 and through aligned openings incover members 40. Arms 12x, 13x of members 12, 13 are fixed to the rearlower end of plate 17 by a bolt 48 which also serves to attach togethercover members 40. A spacer sleeve 50 on the rough bolt 48 is interposedbetween plate 17 and arm 12x. Bolts 44, 46 may have spacer shoulders tokeep members 12, 13 in properly spaced relation.

Mounted on shoulders 12k, 13k and between walls l2j, 13] of members 12,13, is a base plate 52 having a front edge 53 formed with a central flatgroove 54. The rear edge 52a of base 52 may be rounded. Mountedon base52 is a metal cup 55 having a bottom wall 56 from which a cylindricalwall 57 extends upwardly. Bottom wall 56 has a central hole 58. The cup55 is fixed to base 52 by a central stem 61 passing through hole 58 andhole 62 in base 52, and a top flange 63 contacting the top surface ofwall 56. On bottom wall 56 is a central insulating sleeve 65 fitted oversaid upper flange 63. On wall 56 is an insulating apertured disc 66. Onsaid disc is an outer insulating cylincover plate having diametricallyopposed side lugs 76 projecting through suitable notches 77 at the upperend of said wall 57 and through suitable slots 78 in said walls 12j, 13jof frame members 12, 13. The upper end of central sleeve 65 projects upinto a central opening 79 formed in said cover plate as shown in FIGS. 1and 7.

Near the upper ends of walls 12], 13j are formed slots 80. A top fiatdisc 81 has outwardly extending flanges 82 projecting into said slots80. Disc 81 has a central opening 83. Slidably passing through saidopening 83 is a stem 84 of an armature 85. Pinned to the upper end ofstem 84 as at 86 is a spring retainer member 87. Mounted on top of disc81 is a spring supporting dish 88. Between dish 88 and retainer member87 is a conical coil compression spring 90 which biases the armatureupwardly. At the lower end of stem 84 is a thicker cylindical portion 91forming an upper shoulder 92 on which a rubber like annular bumper 93rests. Bumper 93 surrounds the stem 84. Below the thicker portion 91 isa plunger portion 95, the lower end of which is slidably received in theupper end of central sleeve 65. When the coil 130 is deenergized, thespring raises the armature to its uppermost position. At the upper endof plunger 95 is an annular shoulder 96. A metal disc 97 rests on theshoulders 96 and surrounds the thicker armature portion 91. Surroundingthe upper end of plunger 95 is a second rubber like bumper 98 fixed tothe underside of disc 97. Rubber of bumper 93 may be fixed to armature85 to reciprocate therewith and with disc 97.

When coil 130 is energized in the manner hereinafter explained, to pulldown the armature 85, bumper 98 will strike cover 75. When the coil isdeengergized in the manner to be described hereinafter, the spring 90raises the armature 85 and bumper 93 strikes the underside of disc 81.

Disc 97 has a forwardly extending lug 99 projecting into the spaceformed by forwardly recessed wall 31a of the cover 30. A staple drivingblade 100 has a slot 100a near its upper end receiving said lug 99. Saidblade 100 also slides in groove 54 in plate 52 (See FIG.1). Thus, whenthe coil 130 is energized, the armature 85 is moved down to drive astaple from the forward part of a staple magazine 101 to be describedhereinafter.

It is to be noted that the plastic covers the upper end of the forwardor head part of the stapler as shown at 40d (FIGJ). The plastic covers40 also cover the front surface of metal cover 30 as at 40c, but coverportion 40c terminates above slots 33 (See FlG.1

In the lower end of the stapler and between the lower portions ofmembers 12, 13 is the staple magazine 10] which may be of any suitableconstruction. Said magazine 101 way comprise a magazine housing 102having a flat bottom wall 103 from which parallel side walls 104 extendupwardly (See FlG.3). The wall 103 is located at the lower edges 12c,130 of members 12, 13. At the front end of side walls 104 are lugsreceived in slots 33. At the rear end of walls 104 are upright aperturedears 105 receiving a transverse bolt 106 mounted on members 12, 13. Inthe magazine housing 101 is a staple guide 110 having a bottom wall 111fixed centrally to bottom wall 103. Extending up from wall 111 areparallel walls 112. The staples ride on the staple guide and betweensaid guide and the staple magazine housing. The rest of the staplemagazine may be of usual construction for driving the foremost stapledown between the front wall of front cover 30 and the front end of thestaple guide.

Walls 104 of the magazine housing 102 are in vertical planes spacedinwardly of members 12, 13. Mounted on bolt 45 and between members 12,13, for oscillation is a safety switch actuating device 110a. Saiddevice 110a comprise a member 111a having similar, parallel side arms112 in vertical planes passing between walls 104 and members 12, 13.Said side arms 112 are inclined forwardly and downwardly and normallyproject downward below the underside of walls 12a, 130 just behind theplane of ejection of staples. Said arms 112 are interconnected by across portion 113 and have apertured ears through which said bolt 45passes.

Fixed to the upper side of cross-portion 113 is a control strip spring115 having a forwardly extending arm 116 contacting the underside ofmember 59 and a rearwardly extending arm 117 disposed horizontally.Mounted on and between side walls 12a, 13a of members 12, 13 is asupport plate 118 on which is mounted a micro-switch 119 provided withan upwardly extending switch actuator button 120 contacting theunderside of spring arm 117. When the stapler is off a work piece, thebutton 120 is in an inoperative position. When the stapler is placed ona workpiece, member 110a is rotated to depress the button 120 andthereby actuate the micro-switch 119 for the purpose hereinafterappearing.

On plate 17 are a pair of terminals 125, 126 to which conductor wires184, 196 are attached. Plate 17 is notched as at 17a between terminals125, 126. Said wires 184, 196 pass through an opening 129 in plasticcover 40 and form cable 124. A grip bushing 129a in said opening 129holds the cable 124 tightly in place. A tranverse bolt 124a may passthrough aligned holes in portions 12w, 13w of frame members 12, 13within the cover 40.

The electro-magnetic coil 130 is controlled by an electric circuit shownin FIG. 9 of the drawing. This circuit is the same as the circuit shownin FIG. of my US. Pat. No. 3,589,587, except for a change which will belater described. Numerals designating parts of the circuits of FIG. 9herein, where applicable.

All the components of the circuit connected to wires 184, 196 exceptcoil 130 and wires leading thereto and therefrom, are mounted on plate17, and are covered or embedded insulating material.

Normally, when the trigger 18 is not raised, a switch 123, controlled byactuator 29, in in contact with contact 180. When the trigger isactuated, switch 123 disengages from contact 180 and engages contact181.

The difference between the FIG. 10 circuit of the aforesaid US Patentand the circuit shown in FIG. 9 herein, is that wire 205 of the formercircuit, in the present circuit, is broken into parts 205, 205a whichmay be bridged by a switch 300 which is normally open but is closed toconnect wires 205, 205a only when the stapler is on the work piece andswitch member 110a has been rotated in a clockwise direction viewed atFIG. 1 of the drawing herein, to operate the actuator button 120 of themicro-switch 119.

The circuit of FIG. 9 will now be described.

One side of said load coil 130 is connected by wire 182 to a rectifieranode 183 which is connected by wire 184 to a plug. Switch 123 isconnected by wire 185 to a capacitor 186 which is connected by wire 187to one side of a resistor 188. The other side of the resistor 188 isconnected to rectifier 189, by a wire l87ab. Rectifier or anode 189 isconnected by wire 190 to said wire 184.

Contact is connected by wire 191 to a wire l87ab. The other side of loadcoil 130 is connected by wire 192 to the anode side of a gated siliconrectifier or SCR 193. The cathode side of said SCR 193 is connected bywire 194 to one side of a rectifier or diode 195. The other side ofrectifier or diode 195 is connected to wire 196. Resistor 198 isconnected to diode 195 in parallel circuit.

Connected to wire 192 is a wire 200 connected to one side ofa resistor201. The other side of resistor 201 is connected by wire 202 to one sideofa capacitor 203. The other side of capacitor 203 is connected by wire204 to wire 196.

Wire 194 is connected by wires 205,205a in rough switch 309 to a neonlamp 206. Said lamp is connected by wire 207 to contact 181. Wire isconnected to wire 187 by resistor 187a so that resistor 187a andcapacitor 186 are in parallel circuit.

The plug is connected by ground wire 210 to the body 12,13. The wires210, 184, 196 passing from plug P to the tool comprise the line cord orcable 124.

The components of the circuit other than the load coil 130, the triggerswitch 123 and contacts 180, 181 are mounted in any suitable manner onthe insulating plate 17.

The plug has blades 224, 225, 226 connected to wires 210, 184 and 196,respectively.

The load coil is locked in place when the body parts are assembled.

The operation of the circuit will now be described, with the assumptionthat the tool is on the work piece and the switch 300 is closed:

The switch 123 is normally in engagement with contact 180. The capacitor203 charges through rectifier or diode 183, load coil 130 and resistor201, while the tool is not operating. The trigger switch may be closedrandomly and when the trigger switch 123 is actuated and moves intoengagement with contact 181, capacitor 186 draws current and turns onSCR 193 during the negative cycle of alternating current from an outletto which the plug 12a is connected. If the switch should close during apositive half cycle of the supply rectifier or diode 189 prevents flowof current until the line reverses polarity. With the line negative gatecurrent flows from the line through the SCR 193 gate, the switch 123,resistor 188 and rectifier or diode 189 to charge capacitor 186. Currenthas to take this path because diode prevents current flow directly fromthe line in the reverse direction to the switch. SCR 193 will trigger assoon as gate current flows because the SCRs diode is always forwardlybiased by previously charged capacitor 203. With SCR 193 gated on, thedischarge time constant of the resistor 201, capacitor 203 network andSCR 193 is long enough to maintain SCR 193 in conduction until the lineonce more reverses polarity. However, SCR 193 does not conduct until theline turns positive. When line turns positive the neon lamp 206, fires,discharging the capacitor 203 thereby causing the SCR 193 to conduct.

The SCR 193 turns off when the line turns negative again. SCR 193 canonly conduct when the capacitor 186 draws currentnThe delay periodbetween pulses depends on the value of resistor 187a which acts as ableeder resistor across capacitor 186. The larger the valve of saidresistor 1870, the slower the frequency of the pulse.

As long as switch 123 is kept in closed position, in engagement withcontact 181, the tool will operate to drive a staple at predeterminedintervals, repeatingly.

The SCR 193 will always become conductive at the beginning of a positivecycle of the alternating current and will automatically shut off untilthe next pulse.

If the switch is closed and then opened in less time than thepredetermined interval, there will be only one pulse and no furtherpulsing will take place until the switch is closed again.

Opening of switch 123 (from contact 181 to contact 180 cuts outcapacitor 186 and prevents further pulsing).

Upon lifting the tool off the work piece, switch 300 opens and nopulsing can take place. This is a safety feature to prevent ejection ofstaples when the tool is held in the air, that is uplifted from the workpiece.

It will thus be seen that there is provided an article in which severalobjects of this invention are achieved, and which is well adapted tomeet the conditions of practical use.

As possible embodiments might be made of the above invention and asvarious changes might be made in the embodiments above set forth, it isto be understood that all matter herein set forth or shown in theaccompanying drawings, is to be interpreted as illustrative only.

The armature 35 is guided at its lower end in the sleeve 65 of the coil,and at its upper end in disc 81. The plate 97 is disposed between thecoil and said disc. Hence the armature is guided for true up and downmovement, to facilitate its moving the driving blade 100 up and downwithout jamming.

What is claimed is:

l. A staple driving tool comprising a body, a load coil in said body,said coil having a central opening, an armature disposed in said bodyand axially slidable in said hole, for movement by said coil when thecoil is energized, staple driving means fixed to said armature anddisposed at the front of the body, a staple magazine at the lower end ofsaid body, a trigger switch on said body, and circuit means includingsaid coil and switch, to automatically energize said coil upon actuatingsaid switch, and safety switch means in said circuit and located at thefront of the body, to prevent energizing of the coil unless the lowerfront end of the tool is on a work piece in position for stapling, saidbody comprising a pair of symmetrical frame members, said load coilbeing disposed between said frame members, said staple magazine beingdisposed between said frame members, said trigger switch comprising atrigger housing disposed between said frame members, a trigger slidablein said trigger housing, a micro-switch on said trigger housing, meansto actuate said micro-switch upon moving the trigger in said triggerhousing in one direction, and means to fix said staple magazine, saidtrigger housing, said micro-switch said safety switch and said coil tosaid frame members and to fix said frame members to each other.

2. The combination of claim 1, and a pair of insulating cover members onsaid body, said attach means including means to attach said covermembers to said body.

3. A stapler comprising a body, said body comprising a pair of similar,symmetrically disposed, spaced, metal frame members having lowerhorizontally extending portions and vertical portions extending upwardlyfrom the front ends of said horizontal portions, a handleshapedinsulating plate connecting an upper end of the vertical portion of oneof said frame members with the rear end of the horizontal portion ofsaid one frame member, a trigger between said frame members, amicr0-switch above said trigger housing and between said frame members,a trigger slidably mounted in said trigger housing, spring means tolower said trigger; and means to actuate said micro-switch upon raisingsaid trigger.

4. The combination of claim 3, an electromagnetic coil between thevertical portions of said frame members, an armature for saidelectromagnetic coil, slidably mounted therein, spring means to raisesaid armature, a staple driving blade mounted on said armature forreciprocation therewith, and means to fix said trigger housing, saidmicro-switch and electro-magnetic coil to and between said framemembers.

5. The combination of claim 4, a cup receiving said electro-magneticcoil, said cup comprising a bottom wall from which a cylindrical wallextends upwardly, said coil being housed in said cup, a cover on saidcup having lugs extending outwardly from said cover and beyond saidcylindrical wall, and said frame members having part cylindricalportions contacting said cylindrical wall and formed with slotsreceiving said lugs.

6. The combination of claim 5, a base disposed below the bottom wall ofsaid cup and means to fix said base to said bottom wall.

7. The combination of claim 6, a disc disposed in spaced relation abovesaid cup and between said frame members and having edges contacting thepartcylindrical walls thereof, and having outwardly extending lugs, saidpart cylindrical portions having slots receiving said lugs on said disc.

8. The combination of claim 7, an armature slidable in the coil andextending thereabove, a plate fixed to said armature for movementtherewith and disposed below said disc and spaced above said cover, saidplate having a forwardly extending projection, and a staple drivingblade mounted on said projection for reciprocation with said armature.

9. The combination of claim 8, and a pair of bumpers fixed to saidarmature, one above and one below said plate, for contacting said discand cover respectively.

10. The combination of claim 9, a shallow dish on said disc, a coilcompression spring on said shallow disc and surrounding the upper end ofsaid armature, and stop means at the upper end of said armaturecontacted by the upper end of said compression spring, whereby saidcompression spring raises said armature from lowered position, upondisengaging said coil.

11. A stapler comprising a body, said body comprising a pair ofsymmetrically disposed spaced frame members having lower horizontallyextending portions and vertically extending portions extending upwardlyfrom the front ends of said horizontally extending portions, saidupwardly extending portions having part cylindrical outwardly recessedportions, a cup disposed between said part cylindrical shaped portions,said cup comprising a bottom wall from which a cylindrical wall extendsupwardly a load coil housed in said cup having a center hole forslidably receiving a cylindrical armature extending thereabove, a coverat the upper end of said cup and having a center hole, for slidablyreceiving the lower end of said armaturee, registering with armature,center hole in said coil, said cover having lugs, said cup havingnotches receiving said lugs, said part cylindrical portions having slotsreceiving said lugs, and means to attach said frame members to said cup.

12. The combination of claim 11, a disc disposed in spaced relationabove said cup and between said frame members and having edgescontacting the partcylindrical walls thereof, and having outwardlyextending lugs, said part cylindrical portions having slots receivingsaid lugs on said disc, said disc having a central hole therein toslidably receive an upper portion of the armature.

13. The combination of claim 11, a base disposed below the bottom wallof said cup and means to fix said base to said bottom wall.

14. The combination of claim 12, a plate fixed to said armature formovement therewith and disposed below said disc and spaced above saidcover, said plate having a fowardly extending projection, and asubstantially flat staple driving blade mounted on said projection forreciprocation with said armature.

15. The combination of claim 14, and a pair of bumpers fixed to saidarmature, one above and one below said plate, for contacting said discand cover respectively.

16. A staple driving tool comprising a body, an electro-magnetic loadcoil means in said body, means to fix said coil means to said body, saidcoil means having a central hole, an axial armature having its lower endslidably received in said hole and guided by said coil means forvertical reciprocation, upper guide means fixed to the body coaxially ofsaid coil means and having means to slidably receive and guide saidarmature for vertical reciprocation, a member fixed to said armature anddisposed between said coil means and said upper guide means and offsetforwardly of said armature, a staple drive blade mounted on said memberand disposed at the front of the body and parallel to said armature andmeans on said body to guide said drive blade for vertical movement withsaid armature in parallel spaced relation thereto.

17. A staple driving too] comprising a body, a load coil in said body,an armature disposed in said body for movement by said coil when thecoil is energized, staple driving means on said armature, a staplemagazine at the lower end of said body, a trigger switch on said body,and circuit means including said coil and switch to automaticallyenergize said coil upon actuating said switch, means to fix said coil tosaid body, said coil having means to slidably receive and guide thelower end of said armature, upper guide means fixed to the body, toslidably receive and guide the upper end of said armature, said stapledriving means being disposed parallel to and spaced from said armature,and outside said coil and at the front of said body and being fixed tosaid armature between said coil and upper guide means, said bodycomprising a pair of spaced, symmetrically disposed frame members, saidcoil being disposed between said frame members, said upper guidecomprising a disc disposed in spaced relation above said coil andbetween said frame members and above said member fixed to said armature,and safety switch means in said circuit to prevent energizing of thecoil unless the lower front end of the tool is on a work piece inposition for stapling.

18. A staple driving tool comprising a body, a load coil in said body,an axial armature disposed in said body for movement by said coil whenthe coil is energized, said armature comprising a lower portion slidablyreceived in said coil, and a top portion extending above said coil, anupper guide means on the body having a hole to slidably receive said toparmature portion and means on the body having a hole constituting lowerguide means for said lower armature portion, staple driving means fixedto said armature between the upper guide means and lower guide means, astaple magazine at the lower end of said body, a trigger switch on saidbody, and circuit means including said coil and switch to automaticallyenergize said coil upon actuating said switch, and safety switch meansin said circuit to prevent energizing of the coil unless the lower frontend of the tool is on a work piece in position for stapling.

19. The combination of claim 18, said staple driving means comprised asubstantially flat blade and an attaching member mounted to said bladeand to said armature.

20. The combination of claim 19, said attaching member beinghorizontally disposed and spaced between said upper and lower guidemeans.

21. The combination of claim 18, a cup receiving said load coil, saidcup comprising a bottom wall from which a cylindrical wall extendsupwardly, said coil being housed in said cup.

22. The combination of claim 21, and means at the bottom of said cup toguide said drive blade for vertical movement with said armature inparallel spaced relation thereto.

23. The combination of claim 22, said drive blade guide means comprisinga plate fixed to the bottom of said cup and said staple drive bladeguide means being located at the forward end of said plate.

24. The combination of claim 16 wherein said armature has an upperportion of lesser diameter than said lower end thereof, and said coilmeans comprises lower guide means to guide said lower end of saidarmature and said upper guide means guides said upper portion of saidarmature.

1. A staple driving tool comprising a body, a load coil in said body,said coil having a central opening, an armature disposed in said bodyand axially slidable in said hole, for movement by said coil when thecoil is energized, staple driving means fixed to said armature anddisposed at the front of the body, a staple magazine at the lower end ofsaid body, a trigger switch on said body, and circuit means includingsaid coil and switch, to automatically energize said coil upon actuatingsaid switch, and safety switch means in said circuit and located at thefront of the body, to prevent energizing of the coil unless the lowerfront end of the tool is on a work piece in position for stapling, saidbody comprising a pair of symmetrical frame members, said load coilbeing disposed between said frame members, said staple magazine beingdisposed between said frame members, said trigger switch comprising atrigger housing disposed between said frame members, a trigger slidablein said trigger housing, a micro-switch on said trigger housing, meansto actuate said micro-switch upon moving the trigger in said triggerhousing in one direction, and means to fix said staple magazine, saidtrigger housing, said micro-switch said safety switch and said coil tosaid frame members and to fix said frame members to each other.
 2. Thecombination of claim 1, and a pair of insulating cover members on saidbody, said attach means including means to attach said cover members tosaid body.
 3. A stapler comprising a body, said body comprising a pairof similar, symmetrically disposed, spaced, metal frame members havinglower horizontally extending portions and vertical portions extendingupwardly from the front ends of said horizontal portions, ahandle-shaped insulating plate connecting an upper end of the verticalportion of one of said frame members with the rear end of the horizontalportion of said one frame member, a trigger between said frame members,a micro-switch above said trigger housing and between said framemembers, a trigger slidably mounted in said trigger housing, springmeans to lower said trigger; and means to actuate said micro-switch uponraising said trigger.
 4. The combination of claim 3, an electromagneticcoil between the vertical portions of said frame members, an armaturefor said electromagnetic coil, slidably mounted therein, spring means toraise said armature, a staple driving blade mounted on said armature forreciprocation therewith, and means to fix said trigger housing, saidmicro-switch and electro-magnetic coil to and between said framemembers.
 5. The combination of claim 4, a cup receiving saidelectro-magnetic coil, said cup comprising a bottom wall from which acylindrical wall extends upwardly, said coil being housed in said cup, acover on said cup having lugs extending outwardly from said cover andbeyond said cylindrical wall, and said frame members having partcylindrical portions contacting said cylindrical wall and formed withslots receiving said lugs.
 6. The combination of claim 5, a basedisposed below the bottom wall of said cup and means to fix said base tosaid bottom wall.
 7. The combination of claim 6, a disc disposed inspaced relation above said cup and between said frame members and havingedges contacting the part-cylindrical walls thereof, and havingoutwardly extending lugs, said part cylindrical portions having slotsreceiving said lugs on said disc.
 8. The combination of claim 7, anarmature slidable in the coil and extending thereabove, a plate fixed tosaid armature for movement therewith and disposed below said disc andspaced above said cover, said plate having a forwardly extendingprojection, and a staple driving blade mounted on said projection forreciprocation with said armature.
 9. The combination of claim 8, and apair of bumpers fixed to said armature, one above and one below saidplate, for contacting said disc and cOver respectively.
 10. Thecombination of claim 9, a shallow dish on said disc, a coil compressionspring on said shallow disc and surrounding the upper end of saidarmature, and stop means at the upper end of said armature contacted bythe upper end of said compression spring, whereby said compressionspring raises said armature from lowered position, upon disengaging saidcoil.
 11. A stapler comprising a body, said body comprising a pair ofsymmetrically disposed spaced frame members having lower horizontallyextending portions and vertically extending portions extending upwardlyfrom the front ends of said horizontally extending portions, saidupwardly extending portions having part cylindrical outwardly recessedportions, a cup disposed between said part cylindrical shaped portions,said cup comprising a bottom wall from which a cylindrical wall extendsupwardly a load coil housed in said cup having a center hole forslidably receiving a cylindrical armature extending thereabove, a coverat the upper end of said cup and having a center hole, for slidablyreceiving the lower end of said armaturee, registering with armature,center hole in said coil, said cover having lugs, said cup havingnotches receiving said lugs, said part cylindrical portions having slotsreceiving said lugs, and means to attach said frame members to said cup.12. The combination of claim 11, a disc disposed in spaced relationabove said cup and between said frame members and having edgescontacting the part-cylindrical walls thereof, and having outwardlyextending lugs, said part cylindrical portions having slots receivingsaid lugs on said disc, said disc having a central hole therein toslidably receive an upper portion of the armature.
 13. The combinationof claim 11, a base disposed below the bottom wall of said cup and meansto fix said base to said bottom wall.
 14. The combination of claim 12, aplate fixed to said armature for movement therewith and disposed belowsaid disc and spaced above said cover, said plate having a fowardlyextending projection, and a substantially flat staple driving blademounted on said projection for reciprocation with said armature.
 15. Thecombination of claim 14, and a pair of bumpers fixed to said armature,one above and one below said plate, for contacting said disc and coverrespectively.
 16. A staple driving tool comprising a body, anelectro-magnetic load coil means in said body, means to fix said coilmeans to said body, said coil means having a central hole, an axialarmature having its lower end slidably received in said hole and guidedby said coil means for vertical reciprocation, upper guide means fixedto the body coaxially of said coil means and having means to slidablyreceive and guide said armature for vertical reciprocation, a memberfixed to said armature and disposed between said coil means and saidupper guide means and offset forwardly of said armature, a staple driveblade mounted on said member and disposed at the front of the body andparallel to said armature and means on said body to guide said driveblade for vertical movement with said armature in parallel spacedrelation thereto.
 17. A staple driving tool comprising a body, a loadcoil in said body, an armature disposed in said body for movement bysaid coil when the coil is energized, staple driving means on saidarmature, a staple magazine at the lower end of said body, a triggerswitch on said body, and circuit means including said coil and switch toautomatically energize said coil upon actuating said switch, means tofix said coil to said body, said coil having means to slidably receiveand guide the lower end of said armature, upper guide means fixed to thebody, to slidably receive and guide the upper end of said armature, saidstaple driving means being disposed parallel to and spaced from saidarmature, and outside said coil and at the front of said body and beingfixed to said armature between said coil and upper guide means, saidbody comprising a pAir of spaced, symmetrically disposed frame members,said coil being disposed between said frame members, said upper guidecomprising a disc disposed in spaced relation above said coil andbetween said frame members and above said member fixed to said armature,and safety switch means in said circuit to prevent energizing of thecoil unless the lower front end of the tool is on a work piece inposition for stapling.
 18. A staple driving tool comprising a body, aload coil in said body, an axial armature disposed in said body formovement by said coil when the coil is energized, said armaturecomprising a lower portion slidably received in said coil, and a topportion extending above said coil, an upper guide means on the bodyhaving a hole to slidably receive said top armature portion and means onthe body having a hole constituting lower guide means for said lowerarmature portion, staple driving means fixed to said armature betweenthe upper guide means and lower guide means, a staple magazine at thelower end of said body, a trigger switch on said body, and circuit meansincluding said coil and switch to automatically energize said coil uponactuating said switch, and safety switch means in said circuit toprevent energizing of the coil unless the lower front end of the tool ison a work piece in position for stapling.
 19. The combination of claim18, said staple driving means comprised a substantially flat blade andan attaching member mounted to said blade and to said armature.
 20. Thecombination of claim 19, said attaching member being horizontallydisposed and spaced between said upper and lower guide means.
 21. Thecombination of claim 18, a cup receiving said load coil, said cupcomprising a bottom wall from which a cylindrical wall extends upwardly,said coil being housed in said cup.
 22. The combination of claim 21, andmeans at the bottom of said cup to guide said drive blade for verticalmovement with said armature in parallel spaced relation thereto.
 23. Thecombination of claim 22, said drive blade guide means comprising a platefixed to the bottom of said cup and said staple drive blade guide meansbeing located at the forward end of said plate.
 24. The combination ofclaim 16 wherein said armature has an upper portion of lesser diameterthan said lower end thereof, and said coil means comprises lower guidemeans to guide said lower end of said armature and said upper guidemeans guides said upper portion of said armature.